In the field of vision based guidance systems, and more particularly, in the area of automated arc welding, sensor packing has become an area of vital importance and continues to frustrate attempts at developing a truly flexible automated welder. Current sensor design has developed to the point where the sensor itself is as slim as the torch bracket in one dimension, allowing the sensor to proceed the torch through any narrow opening which the torch alone could pass. However, as the first dimension is minimized, so too must the second and third dimensions be increased, thus reducing rotational capabilities as well as limiting how closely the torch may approach an obstacle. Use of this type of sensor on an automated welding system requires an operator to manually weld those inaccessible areas which are the most difficult to reach.
Maneuverability of the torch could be enhanced by moving the sensor to a more remote location, further removed from the welding torch. While this alternative would increase torch accessibility to confined areas, it is recognized that absent any special preparatory action, the reflection coefficient of the workpiece is highly variable and considerable energy density is required to insure that a spot of light is established. The amount of light received by the sensor is a function of the distance between the spot of light and the sensor, thus as the distance increases, more power is required from the light source. Increased power necessarily dictates an increase in physical size that very well may offset the maneuverability gained by moving the sensor further from the welding head.
Additional advantages can be found in removing the sensor from the extremely harsh environment of the welding torch. For example, special cooling considerations may not be necessary, electronic components, being especially sensitive to heat could be constructed from less costly solid state components, as the temperature extremes would be less drastic.
The present invention is directed to incorporating the advantages and overcoming the problems as set forth above.